Amnesia is a partial or total loss of memory caused by biological or functional causes. Biological causes can involve brain damage related to trauma, disease or drug use, while functional causes can be caused by psychological defense mechanisms.
When a person suffers from amnesia, they may have difficulty remembering past places or stages, as well as specific details. Other people, however, cannot remember new information, although they keep their past memories intact..
There are many types of amnesia depending on the causes and the nature of the disease progression. The main types of amnesia are anterograde amnesia and retrograde amnesia, and they are not mutually exclusive. Other types of amnesia are also recorded due to their specificity and nature..
We speak of anterograde amnesia when the patient is unable to remember new information. Recent events and information that must be stored in short-term memory to be converted into long-term memory disappear. However, the past events leading up to the situation that triggered the amnesia can be remembered. Normally, this is the result of a brain trauma that involves the hippocampus, the fornix or the mammillary bodies, fundamental structures for our memory..
In retrograde amnesia, unlike in the previous one, there is an inability to remember events that occurred before this condition affected us, although events that have occurred afterwards can be remembered. Especially, it is the events that have occurred just before the amnesia came that are least remembered, while the oldest memories are usually kept. This can occur both due to trauma and diseases that affect structures related to long-term memory such as the hippocampus and temporal lobes. Both anterograde and retrograde amnesia can be experienced at the same time.
It is a total temporary loss of short-term memory and depending on the severity, also long-term memory. The person stops remembering recent events or verbal information, unable to create new memories or evoke anything that happened beyond the last few minutes. However, identity, language function, and perceptual, visual, spatial and social skills are preserved. This becomes very confusing and is usually accompanied by a state of anxiety, but does not usually last more than a day. It is not a very frequent condition and usually occurs in people between 56 and 75 years old, for multiple causes such as cardiovascular problems, migraines or some kind of epileptic event.
Wernicke-Korsakoff psychosis is a progressive memory loss due to prolonged use of alcohol. Generally, it is accompanied by other neurological dysfunctions such as loss of motor coordination or loss of sensation in the feet and fingers. It can also be caused by malnutrition, specifically by the loss of vitamin B1.
It is a type of amnesia in which the patient is unable to remember personal information perceived as negative or stressful. The causes of this type of amnesia are psychological, they are not due to diseases or brain trauma. Patients do not normally experience an identity crisis, but live in a trance state in which they may develop depersonalization in an effort to block out a stressful experience..
It can be repressed memory, when there is no ability to access information about a traumatic event, although the information is stored in long-term memory.
We speak of dissociative fugue or state of flight, when the person suffers a loss of memory, including their identity, traveling far from their family environment and even forming a new identity. They are the result of experiencing traumatic or highly stressful situations. It is a very rare situation.
It is the inability to remember childhood events due to the immaturity of certain areas of the brain in their early stages. This amnesia usually covers those events that occur from the person's birth to the first four years of life.
If you or someone you know experiences some of the symptoms of memory loss, do not hesitate to consult a professional.